Sound producing apparatus



Oct. 30, A1934. R v NQRTHEY 1,979,048

SOUND PRODUCING APPARATU S Filed Dec. 12, 1932 Patented Oct. 30, 1934 t UNITED" STATES PATENT OFFICE SOUND' PRODUCINQ APPARATUS ARodney V. Northey, Toronto, Ontario, Canada;

Application December 12,1932, Serial No. 646,799- 13 claims. (o1. 116' 147) invention relates' to sound producingl apparatus of the diaphone type in which a hollow vpiston is vibrated in a cylinder having orifices vin its wall, the piston also having oriiices which, by the vibration of the piston are alternately brought into and out of `alinement with the orices of the cylinder, thus controlling the ow of a gaseous uid to cause a rapid succession of puffs to produce a musical note.

In the presentinventionthe problem is to produce a sound producing device particularly adapted for use on railway locomotives on which, for vcertain reasons, it is desirable to use compressed air to vibrate the piston and steam from `1li the locomotive boiler to produce the sound.

In such installations, if apparatus of the type shown in United States Patent 1,789,387 were employed, the very considerable difference in temperature between rthe air and steam would result in unequal expansion of the different parts of the apparatus which wouldmaterially and ad versely affect the operation.

5 My object therefore is to devise I:apparatus which will overcome the difficulty referred to,

425 which may be cheaply produced and which is economical in operation.` l

I'attain my object by `means of a construction which may be briefly described as follows. The

driving air cylinder is spaced from the steam cyll 30. inderand their only connection Iis by means of tie `bolts and spacers of relatively small cross sec- Vtional area, and therefore of small conductive capacity. l

`Further the air` piston and steam piston are connected only Vby a piston rod which is also of relatively small crosssectional area. As `a further protection against the transfer of heat from '.the steam end to the air end, the exhaust air `from the air cylinder is `exhausted into the air piston, which is hollow and open at the end adjacent the steam cylinder. The exhaustfrom the hollow steam pistonpasses into the horn, which is directed away fromthe air cylinder.

YThe device is `also simplified, cheapened and improved in operation by. casting in the cylinder an annular distributing chamber for the sound producing' fluid, which is open at its outer end, and by providing an annular closure with which the horn may be connected. Asimilar arthe gaseous fluid; used in the motive part of the Y apparatus.-

. The invention is hereinafter more fully describedl and is illustrated in the accompanying `ddrawingin which .ports 10 and 11.

rangement is also provided for the distribution of` Fig. 1 is a longitudinal section, partly in elevation, of the apparatus showing the air piston at the rearward end of its stroke;

Fig. 2 a similar view of part of the device showing the air piston at the forward end of its stroke; and

Fig. 3 a front elevation.

In the drawing like numerals of reference indicate corresponding parts in the diierent figures.

Referring to the drawing l is the cylinder of the motive part of the apparatus. This cylinder has its bore formed of two different diameters. The outer end of the cylinder is closed by the cover 2 secured in place bythe bolts 3. In the 70 cylinder is fitted the hollow piston 4, which is also of two different diameters. There is thus a 'chamber of `cylindrical form behind the piston anda chamber of annular form and lesser cross sectional area in front of the piston. With the annular. chamber communicates the annular port 5 communicating by means of passages 6 with the annular chamber 7 formed in the face of the cylinder remotefrom the cover 2.

An annular cover 8 is secured to this face and 80 closesthe chamber 7. A pipe fitting 9 is formed on this cover which serves as a connection between the chamber 7 and a pipe supplying air or other gaseous working uid.

Also in the wall of the cylinder having the larger internal diameter are formed the annular The former is opened by the piston head or enlargement when the piston is at `the-forward end of its'stroke and the latter is opened at the rearward end of the piston stroke. Passages 12 connect the ports. In the piston head are formed the annular ports 13 and 14, the former communicating'with the interior of the hollow piston through the holes 15 and the latter with the annular chamber in front of the piston through the holes 16. A When the piston is at or near the forward end of its stroke the exhaust port 13 is in communication with thel port `l1 and exhaust from behind the piston to its interior takes place through the port 10, passages 12, port 11, port 13 and holes l5. See Fig'. 2.

Aircompressed in the annular chamber by the moving piston then drives back the piston till the port 14 in the piston communicates with the port 11, when air enters the; annular chamber through the port 5 and from the annular chamber fiows through the holes 16, port 14, port 11, passages 12 and port l0 to the cylindrical chamber behind the piston. The pressure before and 1l(` ifo behind the piston is thus equalized and the piston is shot forward again to the exhaust position, since the area of the rear end of the piston, exposed to pressure is much greater than that of the annulus at its forward end exposed to pressure. Thus the piston is rapidly vibrated as long as a driving iiuid, which' will usually be air at a pressure of about 100 lbs. to the square inch, is supplied to the chamber 7.

The actual sound producing apparatus comprises a cylinder 17 and a hollow open ended piston 18. The pistons 4 and 18 are connected by the piston rod 19.

The inner wall 20 of the cylinder 17 has the sound producing orices 21 formed therein. The

wall of the piston is also provided with orificesv 22. The sound is produced by the reciprocation of the piston which causes its sound producing orices to coincide at regular intervals with the .orifices of the cylinder, thus producing a series ally be high pressure superheated steam. This uid is supplied to the orifices 21 from the chamber 23 which surrounds the wa1l20 and opens through the outer face of the cylinder 17. A

rcover 24 secured tothe cylinder 1'7 by the bolts 25close`s the chamber, and also has the horn 29 formed on or secured thereto. The chamber "is provided with an inlet 26 for connection vwith. a steam supply pipe. The cylinders 1 `and 17 are secured togetherby the bolts 27. and their spacing vmaintained by the spacing sleeves 2S through which' the'bolts pass. From the above description it will be seen that the actual heatconductiveconnection between the driving and sound' producing ends of the Vapparatus is reduced to Varhinrnum, while air may pass freely' between them to carry awaythe heat from the sound producing end. Further-the cool exhaust `air' Afrom the Adriving end is discharged into this'space, adding tothe cooling effect, while the hot exhaust from the sound 4producing* end is directed away from the device. y

Owing to the entire sepa'. ration of the driving piston and the driven piston exhausting the driving air into 'theinterior ofthe hollow driving piston cannot prejudiciallyiaffect the sound' production as was' the case in earlier forms of dias'ound producing piston. Y. Y

The general construction is also"verys1mple comprisingV simple, easilyV machined andlassern-y bled parts.

producing orices in'its wall'adapted to be brought "t "h the orifices in the c linder Into almemen W11; y rmovable vclosure closing -the larger end of the by the reciprocation of the piston; a chamber for a sound-producing gaseous fluid formed about the cylinder;v a driving piston; a piston rod'` connecting thelt'wo pistons; a cylinder for the driving piston spaced from the cylinder of the driven piston; f means connecting the cylinders in spaced l relationship?and'ports in the driving piston and 'the'vvalls'of 'its cylinder controlling the admission 1 paratus.

2. A sound producing device according to claim` 1 in which the driving piston is hollow and open at one end to the atmosphere and the cylinder therefor open at the saine end and in which the exhaust of the driving fluid takes place into and through the interior of the piston and through the open end of the rst-mentioned cylinder.

3. A sound producing device according to claim 1 in which the driving piston is hollow and has an open end and the cylinder thereof has also an open end facing the cylinder of the driven piston and in which the exhaust of the driving fluid takes place into and through the interior of the driving pistonand through the open end of the first-mentioned cylinder. W 4. -A sound producing device comprising a hollow ndriving Ypiston-having an enlarged head and being open at the smaller end; a cylinder having vparts of different diameter to receive the parts of the piston of corresponding diameter, thecylinder being closed -at its larger end whereby a cylindrical chamber is formed-behind the pistonand an annular chamber infrontof the head; a supply port in `the cylinder wall for the driving viiuid, opening into thesaid annular chamber when the piston is at-or near the rearward endofits stroke;

aport in the-cylinder wall open'when the piston s atthe forward' en'd lof its stroke; an intermediate port in the `cylinder wall; a lpassage in the ports ;a'n exhaust port inthe piston wall towards 'its rear end opening into the interior of the piston; an inlet port in the wall of the pistonin constant communication with the annular charn- `cylinder wall connecting the two last `'mentioned "105 ber, theportsbeingpositioned `and-proportioned no reciprocating Ldiaphone. type Aspaced from but115 l-connectedwitlithecylinder aforesaid; anda connection between the piston aforesaid andthe reciprocating -part of the soimd producingap- -5. Al'sound producing device comprising a hollow driving piston having'an enlarged head and VVbeing openat the smaller end; a cylinder r.having parts-'of different diameter'to receive the parts .of the piston fof correspondingdiameter, aL removable closure closing the larger end of the cylinder; an.. phone `in which the an. exhausted into the holfannlar inlet chamber `for drivingrfluid formed 10W piston passed 'into and through thekhollow in the cylinder and opening through the face of the smaller end thereof; a removable coverclosing said chamberports in the pistonand cylinder walls controlling the vadmission and exhaust of the drivingl fluid; sound producing apparatus of the reciprocating diaphone' type spaced from .but

*connected with the cylinder aforesaid; and a cylinder; an annular inlet chamber for driving Avfluid formed inthe cylinderandopening through the face of the-smaller end thereof; a removable,

cover closingV said chamber; Vav pipe fitting integral with the said cover for forming a connection `between the chamber-andja'supply pipe;r ports in the-piston and cylinder-'walls controlling the admission and exhaust of the driving vffluid';sound/i150 Y ce producing apparatus of the reciprocating diaphone type spaced from but connected with the cylinder aforesaid; and a connection between the piston aforesaid and the reciprocating part of the sound producing apparatus.

7. A' sound producing device comprising a cylinder having sound producing orifices in its wall; a hollow driven piston adapted to reciprocate in said cylinder, open at one end and having sound producing orifices in its wall adapted to be brought into alinement with the orices in the cylinder by the reciprocation of the piston; a chamber for a sound-producing gaseous iiuid formed about the cylinder communicating with the orifices in the cylinder wall and opening through the end face of the cylinder wall; and an annular closure for said chamber secured to the said Wall. o

8. A sound producing device comprising sound producing apparatus of the reciprocating diaphone type including a stationary and a reciprocating part; a reciprocating motor operating with a gaseous driving uid and including a stationary and a reciprocating part, the motor and sound producing apparatus being entirely independent units; a direct connection between the two reciprocating parts; and means detachably holding the stationary parts in spaced relationship.

9. A sound producing device comprising a cylinder having sound producing orices iri-v its wall; a hollow driven piston adapted to reciprocate in said cylinder, open at one end and having sound producing orifices in its wall adapted to be brought into alinement with the orices in the cylinder by the reciprocation of the piston; a

lchamber for a sound-producing gaseous fluid formed about the cylinder communicating with the orifices in the cylinder vwall and opening through the end face of the cylinder wall; an`

annular closure for said chamber removably secured to the said wall; and a horn carried by said closure.

10. A sound producing device comprising sound producing apparatus of the reciprocating diaphone type including a stationary and a reciproeating part; a reciprocating motor operating with a gaseous driving uid and including a stationary and a reciprocating part, the motor and sound producing apparatus being entirely independent units; a direct connection between the two reciprocating parts; and a skeleton connection between the stationary parts holding them in spaced relationship and permitting the free passage of air between their adjacent surfaces.

1l. A sound producing device comprising sound producing apparatus including a stationary and a reciprocating part; a reciprocating motor operating with a gaseous driving uid and including a stationary and a reciprocating part and an exhaust outlet from the motor directed towards the sound producing apparatus, the motor and sound producing means being entirely independent units; means connecting the reciprocating parts; and means connecting the stationary parts in spaced relationship.

12. A sound producing device comprising sound producing apparatus including a stationary and a reciprocating part; a reciprocating motor operating with a gaseous uid and including a stationary and a reciprocating part; an exhaust outlet for the sound producing mechanism directed away from the driving apparatus, the motor and sound producing apparatus being entirely independent units; means connecting the reciprocating parts; and means connecting the stationary parts in spaced relationship.

`13. A sound producing device comprising sound producing apparatus including a stationary and a reciprocating part; a reciprocating motor operating with a gaseous iiuid and including a stationary and a reciprocating part; an exhaust outlet from the motor directed towards the sound producing apparatus; an exhaust outlet for the sound producing mechanism directed away from thel driving apparatus, the motor and sound producing apparatus being entirely independent units; means connecting the reciprocating parts; and means connecting the stationary parts in spaced relationship. 

